The present invention relates to a photographic printing apparatus capable of reading and writing data on magnetic recording tracks on a negative film.
A common photographic printing apparatus is designed for scanning and printing images on a negative film transferred at equal intervals of time.
Also in the common photographic printing apparatus, the negative film has to be advanced at a constant speed for carrying out the reading and writing of data on its magnetic recording tracks without fault.
For allowing both exposure and reading operations in parallel, the common photographic printing apparatus has a film loop section disposed between an exposure station and a magnetic head.
The film loop section however requires a considerable size of space for installation in the photographic printing apparatus. This will increase the overall size of the common photographic printing apparatus, thus limiting the available space of a small sized print shop.
Another conventional photographic printing apparatus is provided with a means of forward and backward movements of a negative film so that the exposure and scanning operations are executed during intermittent transfer of the film and the operations of reading and writing of data are conducted during constant speed transfer thereof.
The forward and backward movements of the negative film will however take a considerable length of time, although the film loop section of the previous apparatus is not needed. Those movements may also cause the negative film to be injured.
It is an object of the present invention, in view of the above description, to provide an improved photographic printing apparatus in which the reading and writing of data on a negative film are carried out with accuracy without, the use of a traditional film loop section but with a minimum number of forward and backward transfer movements.